Projectile



TIS. WILKINSON.

PROJECTILE.

APPLICATION FILED SEPT-'4, 1912.

' 1,371,207. Patented Mar. 8,1921.

V FM b INVENTOR.

TS-mfg.

umrsn sr res THEODORE s'. WILKINSON, or wasrnncrr oiv," msrnrcr orCOLUMBIA.

T 0 all whom it may co'naern: r V Be it known that I, THEODORE S.WILKIN- soN, a citizen of the United States residing at Washington, inthe District of olumbia, have invented-certain new and usefulImprovements in Projectiles, of which the following is a specification.vI This invention relates to improvements in projectiles and in its moreintense aspect to projectiles particularly adapted for use in combatingsubmarines and the like.

One of the objects of the present invention is to provide a projectileor shell of the above character adapted to enter the water at alow-angle flight withoutricocheting.

A further object is to provide a shell of the above character whichwillmaintainits flight when striking thewater and'continue its truetrajectory underwater. V

A further object is to provide a simple and practical shell having theabove char- 7 acter'istics' adapted to explode ata predetermined timewith respect to the moment at I which it strikes the water, thatis;'either by impact with the water or after having traversed a certaindistance under water or after having reached a predetermined depth- 7projectile of the above general character having relatively few-partswhich will be inexpensiveto manufacture and whichwill 'be' reliable andefficient in use and operation.

Other obj ectswill 'be part obvious from the annexed drawings and inpart'indicated in connection therewith by the following analysis of'thisinvention.

partsand in the unique relations of the members and in the relativeproportioning and disposition thereof; all as more completely outlinedherein.

To enable others skilled in the art so fully been annexed as a part ofthis disclosure and in such drawings, like characters of refer- VSpecification of Letters Patent." Application filed September 4, 1917 Ser'ialNo. 189,661;

This invention accordingly consists in the I features of construction,combmatlon of.

ted Mar. 8, 1921;

-ence denote'corresponding parts throughout allthe views, of which:

Figure 1 is a longitudinal sectional'view of the complete shell. r I

Fig. 2 is a front view thereof.

1 Fig. 3 is a diagrammatic View.

It may-have been attempted to" make a non-ricochetlng shell byeliminating the ogival point or truncating the same to re-f duce thetangential contact at the forward end of the shell with the surfaceofqthe water.

The truncated ogival point, however, is

not satisfactory in that-it will not-continue" its trajectory after themoment of the, impact with thewater,andthe shell will probably ricochetif it strikes the water at'an angle less than ten degrees.

It 's found by experience that shell or ashell of substantially plaincylindrical contour will overcome-these and other objections andwill'not ricochet at an, angle above three degrees; It has been;demonstrated that shells of this characterhave" given a non-ricochetaction at two degrees and less in nearly half of the experiments tried.

Other types of shells may have been detory 1n use.

vised adapted to avoid ricochetin'g and continue their trajectory afterstriking the ;wa-

-A'high explosive shell ofgeneral cylin-ii,

drical contour may also have'been devised but not with the purpose 'of'maintaining-its true trajectory'Iafter striking the water. Neither werethey equipped with anexplo' the Wa signed to overcome these and'other'objections'and produce a simple, non-ricocheting and practical shell ofgeneral cylindrical contour adapted to explode at a predeter- V sivedevice adapted to. explode; the shell at a-' predetermined and desiredinstant-with respect to the moment of the impact with 1 The presentinvention is therefore dewith a screw plug 7 closing the explosivechamber 8. The centralpart of the screw plug is provided with aremovable. exploding device or detonator 90f any desired type adapted toset ed a priming charge within a tube 10 axially disposed within theshell. V The detonator is preferably of the delayed action type, thatis; it .is so constructed as to'explo'de the charge at a certaindefinite time after the moment of impact and while the projectile isstill maintaining its trajectory, as distinguished from that type adapted to' explode the shell after the same has sunk a predetermined depthbelow the surface. Although it is understood that either of these typesmay be'used, an impact type of detonator may be substituted adapted toexplode the charge on impact with" the water.

It has been, found by experience that 'shells'ofthis character willmaintain-their I trajectory for a 'distanceof 100 to 200 feet underwater and as above stated will not ricochet at an angle above threedegrees. Thus, projectiles of this type are found advantageous in useagainst submarines in whichthe shell striking the water at a low anglewill continueits flight and explode in 7 close proximity to the boatwhile the ordinary pointed or semi-ogival' shell would ricochet out'ofthe water, or, if continuing under the water would trend to one side orthe other without injury to the boat attacked.

In Fig. 3 there is illustrated diagrammatically'the effect of an ogivalshell striking the water, as well as a shell of the type embodying thesubject of this invention. The ogival shell 11 having a curvature at itsforward end may be assumed to strike the water at'a tangent to thecurvature, pressing the water slightly ahead thereof forward of thepoint -of tangency therebytoraise the nose or point of the shellupwardly and usually to one side, resulting in ricochet from the water!In the flat-nose shell 12, the water isengaged by the forward flat endso that its lower edge would theoretically form a turning point.The'loc-ation of the center of gravity of the shell and its momentum ini the normal direction of its trajectory will,

however, counterbalance this turning effect and cause'the shell to enterthe water witha V out ricocheting and to continue in its true 7trajectory under water, as indicated by the dotted line. v 7

It is thus seen that the present invention is simple, practical,reliable and particularly adapted for use in combating submarines inthat it primarily maintains its trajectory after striking the water andexplodes at a predetermined time with relation to the moment of impactwithout ricocheting.

"'VVithout further analysis, the foregoing will so fully reveal the gistof this invention that others canbyap'plying current knowledge readilyadapt it for the various applications without omitting certaln featuresthat, from the standpoint of the prior art,

fairly constituteessential characteristics of surface so as to preventricocheting on strikin the water at a low an de and to maintaintheprojectile in its true trajectory under Water. I

1 2. A projectile having a body portion of general cylindrical shape,and a rigid noncompressible plug at the forward end of said bodyportion, the end 0% said cylindrical 'body portion and thc' face of saidplug forming a flat unbroken surface so as to prevent ricocheting onstriking the water ata low angle, and to maintain the projectile in itstrue trajectory under water.

3A fiat=nose projectile having a body 7 portion of general cylindricalshape throughout its, length and provided with an exploslve chamber, arigid plug at the forward end of the body portion having aflatsubstantially unbroken surface forming a right angle with the walls ofsaid body portion, and an explosive devicelocated within said "plug,adapted to'explode the charge after the shell has traveled apredetermined distancein its true trajectory under water.

t- Signed at Washington, D. C., this 9th day of August, 1917. i

T. s. WILKINSON,

